Using the Connections Tool

Top  Previous  Next

Connections is a network tool that lets you obtain information about current TCP/IP connections.

You can use the Connections tool to query detailed listings of all TCP and UDP sockets on your system, including the local and foreign addresses and state of TCP connections. It also reports the icon and name of the process that owns each socket.

To use the Connections tool, do the following:

1.Select the Connections tab.

 

The Connections tool displays the results in the Response area.

 

2.Set in the Options dialog box any of the options you want to use:

 

TCP

 

When this option is checked, the Connections tool queries a list of active sockets for TCP.

 

UDP

 

When this option is checked, the Connections tool queries a list of active sockets for UDP.

 

Host names

 

When this option is checked, the Connections tool uses the numeric host address associated with the socket to look up the corresponding symbolic host name.

 

Port names

 

When this option is checked, the Connections tool uses the numeric port number to look up the corresponding symbolic port name.

 

New connections in color

 

When this option is checked, the Connections tool displays new connections in color. A color-selection dialog box allows you to choose a specific color value. You can choose a color from either a set of basic or custom color palettes.

 

Refresh every [n] sec

 

When this option is checked, the Connections tool updates the results in the Response area every n seconds.

 

3.Click the Refresh button to update the results in the Response area.

The possible state values for TCP sockets are as follows:

CLOSED

 

Closed. The socket is not being used.

 

LISTENING

 

Listening for incoming connections.

 

SYN_SENT

 

Actively trying to establish connection.

 

SYN_RCVD

 

Initial synchronization of the connection under way.

 

ESTABLISHED

 

Connection has been established.

 

FIN_WAIT1

 

Socket closed. Shutting down connection.

 

FIN_WAIT2

 

Socket closed. Waiting for shutdown from remote.

 

CLOSE_WAIT

 

Remote shutdown. Waiting for the socket to close.

 

CLOSING

 

Closed, then remote shutdown. Awaiting acknowledgment.

 

LAST_ACK

 

Remote shutdown, then closed. Awaiting acknowledgment.

 

TIME_WAIT

 

Wait after close for remote shutdown retransmission.

DELETE_TCB

Delete TCB.

Tips:

You can right-click the Response area to display the pop-up menu.
You can disconnect any connection by choosing Terminate from the pop-up menu.

Note:

Looking up the corresponding symbolic host name for each host address can significantly increase the time it takes to complete a query.
To see icons of system processes you must run NetInfo with administrative privileges.

Connections example:

connections